This invention relates generally to a vortex type flowmeter and more particularly to a vortex flowmeter having a photoelectric, rotor-velocity modular sensing system and a spoiler system to improve the down side response time of the meter assembly.
A vortex flowmeter generally consists of a confined, generally inverted frustro-conical vortex chamber with a tangential inlet to the vortex chamber and a central outlet. The vortex causes fluid flowing into the chamber to swirl in a generally helical fashion toward the outlet conduit to cause the fluid to increase in velocity as the diameter of the flow path is decreased. Thus, a vortex flowmeter has the tendency to increase the velocity of the fluid through the meter as it is being measured. Typically, a moveable unit is provided in the chamber, which unit is acted on by the fluid in the chamber. A measuring system is provided to sense the movement of the movable unit.
In prior flowmeters, such as is disclosed in a patent to Dabanian, et al., U.S. Pat. No. 3,937,081, issued Feb. 10, 1976, for Vortex Flowmeter, the light emitting diode is mounted within one of the cover members while the phototransistor is mounted in the other cover member, these members forming the vortex chamber described above. With this system, certain manufacturing operations are required to form the mounting apertures within the cover members. Also, the conductors from one of the diode or phototransistor must be led from one cover member to the other to provide a single-side electrical connection to the external display circuitry.
With the system of the present invention, it is contemplated that the interior vortex cavity is provided with a toothed rotor and a light-emitting diode-phototransistor modular sensing arrangement whereby the diode-phototransistor sensing system, with the associated circuit elements, are mounted in a module which is easily removed from the body cavity for replacement. Also, the phototransistor, light-emitting diode and circuit elements are potted within the module to insure that fluid or other contaminant does not contact the circuitry.
Accordingly, it is one object of the present invention to provide an improved vortex flowmeter.
It is another object of the present invention to provide an improved vortex flowmeter having an improved rotor rotation sensing arrangement.
It is a further object of the present invention to provide an improved vortex flowmeter having an improved rotor mounting arrangement.
It is a further object of the present invention to provide an improved vortex flowmeter having a modular light-emitting diode and phototransistor arrangement which is easily removed for replacement.
It is a further object of the present invention to provide an improved rotor rotation sensing arrangement which is inexpensive to manufacture and reliable in use.